File or rasp



J. RIDGE. PILE 0R MSP.

Patented Deo. 10J 1889i MMM (No Modl.)

UNITED STATES PATENT OEEIcE.

JOHN RIDGE, OF'NASHUA, NEIN HAMPSHIRE.

FILE OR RASP.

SPECIFICATION forming part of Letters Patent No. 416,805, dated December 10, 1889. l Applicationled October 24, 1889. Serial No. 328,025. (No model.)

To aZZ whoml it may concern:

Be it known that I, JOHN RIDGE, a citizen of the United States, residing at Nashua, in the county of Hillsboroughand State of New Hampshirehave invented certain new and useful Improvements in Files or Rasps; and I do hereby declare the following tobe a full, clear, and eXact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention consists in an improved article of manufacture-to Wit, a file or rasp, or a combined file andA rasp, coated with a metallic substance which is not liable to rust or corrode, such files or rasps being by the means stated prevented from having, their workingsurfaces more or less filled and clogged with filings of horses hoofs, metal, or other substances upon which they are used, and thus soon rendered comparatively useless.

Heretofore files and rasps, or combined files and rasps, have been finished ready for being placed in paper' packages and put upon the market by oiling their surfaces to prevent t-hem from rusting. This mode of Iinishing files and rasps or combined files and rasps, however, is objectionable in that the oil'renders the surfaces sticky, and thus horse-hoof and metal lings, as well as other filings, will soon more or less clog up the teeth, rendering the Working-surfaces of these implements smooth and 'glossy and prematurely ineffectual. By my invention I not only prevent such implements fromrusting, but also render them capable of freely shedding the iilings of the metal and other substances upon which they are'used.

In the drawings, Figure I shows acombined file and rasp, this figure presenting in plan View the working-surfaces a a of a rasp as ordinarily constructed. Fig. 2 is a longitudinal section, on enlarged scale, in the line of Fig. 1, and exposes to view aportion of the working-teeth a2 of an ordinary file formed upon the tile-blank A obverse to the surfaces d a.

Having constructed a rasp or file or a combined lile and rasp, as the case may be, I then, as a finish therefor, treat the same to a bath or Wash or coating of, preferably, a copper alloy consisting of a solution of blue vitriol (sulphate of copper) and tin in water. This coating solution (represented at a3 in Fig. 2 in exaggerated view) having been applied to the working-surfaces of les and rasps constitutes a dry finish for these implements, serving to prevent the same from rusting, and also rendering them freely capable of shedding filings in the act of use. I thus use a non-oxidizable deposit of metal solution,-

as indicated at a3, which soon dries upon and over the working-surfaces of tiles and rasps,

-which prevents them from rusting, although made of oxidizable metal, and also allows them to freely shed filings,said metallic de-v cial unoxidizable coating, as it is a file or rasp' or combined file and rasp coated as described that constitutes my invention.

What I claim is- As an improved article of manufacture, a file or rasp or combined file and rasp which has an exterior coating of unoxidizable metal,

` substantially as and for the purpose described.

In testimony whereof I hereunto affix my slgnat-ure in presence of two Witnesses.

. JOHN RIDGE.

Witnesses:

' R. T. SMITH,

C. A. MASON. 

